The wireless network includes terminals and base station. The terminal capability of aggregating spectrum resources for communications on all the resources at the same time is fundamentally limited, and is generally much smaller than the eNB capability of communication on possibly vast amount of spectrum resources.
Currently the amount of spectrum that a terminal may access at a time through carrier aggregation is limited to 100 MHz using five 20 MHz carriers. However, the eNB is expected to be able to support much wider bandwidth, e.g., 400+ MHz bandwidth (at the C-band), or 4 carriers with each 2.16 GHz wide (at 60 GHz, similar to IEEE 802.11ad).